Hi, I need someone's help very much on XML Schema Having the following example :
<header>
<a/>
<header>
<body>
<sub><a/>...</sub>
</body>
If it is possible to express in XML schema definition language that element
<a/> may be omitted in <sub>, but _if_ it it is present in <header>, or element
<a/> _must_ be present in <sub> if not present in <header>?
Thanks in advance,
Vadim Solonovich
